Polymarket faced an attempted theft of at least $10 million through stolen debit cards earlier this year, while CEO Shayne Coplan urged employees to prioritize growth and downplayed compliance concerns, according to a Wall Street Journal investigation. The report said fraudsters targeted the platform from February 2026 and that Checkout.com rejected more than 80% of Polymarket US deposits it handled as fraudulent, compared with an industry standard of roughly 1%. A separate late-July attack reportedly exposed nearly 500 users' accounts through stolen personal information. The report did not establish how much of the attempted theft succeeded.